Umbilical cord blood cell transplantation after brain ischemia--from recovery of function to cellular mechanisms

Hypothermia combined with neuroprotective adjuvants shortens the duration of hospitalization in infants with hypoxic ischemic encephalopathy: Meta-analysis

Objective: Therapeutic hypothermia (TH) is the current standard of care for neonatal hypoxic-ischemic encephalopathy (HIE), yet morbidity and mortality remain significant. Adjuvant neuroprotective agents have been suggested to augment hypothermic-mediated neuroprotection. This analysis aims to identify the classes of drugs that have been used in combination with hypothermia in the treatment of neonatal HIE and determine whether combination therapy is more efficacious than TH alone. Methods: A systematic search of PubMed, Embase and Medline from conception through December 2022 was conducted. Randomized- and quasi-randomized controlled trials, observational studies and retrospective studies evaluating HIE infants treated with combination therapy versus TH alone were selected. Primary reviewers extracted information on mortality, neurodevelopmental impairment and length of hospitalization for meta-analyses. Effect sizes were pooled using a random-effects model and measured as odds ratio (OR) or mean difference (MD) where applicable, and 95% confidence intervals (CI) were calculated. Risk of bias was assessed using the tool from the Cochrane Handbook for Systematic Reviews of Interventions. Results: The search strategy collected 519 studies, 16 of which met analysis inclusion criteria. HIE infants totaled 1,288 infants from included studies, 646 infants received some form of combination therapy, while 642 received TH alone. GABA receptor agonists, NMDA receptor antagonists, neurogenic and angiogenic agents, stem cells, glucocorticoids and antioxidants were identified as candidate adjuvants to TH that have been evaluated in clinical settings compared to TH alone. Length of hospitalization was significantly reduced in infants treated with combination therapy (MD -4.81, 95% CI [-8.42. to -1.19], p = .009) compared to those treated with TH alone. Risk of mortality and neurodevelopmental impairment did not differ between combination therapy and TH alone groups. Conclusion: Compared to the current standard of care, administration of neuroprotective adjuvants with TH reduced the duration of hospitalization but did not impact the risk of mortality or neurodevelopmental impairment in HIE infants. Meta-analysis was limited by a moderate risk of bias among included studies and small sample sizes. This analysis highlights the need for preclinical trials to conduct drug development studies in hypothermic settings to identify relevant molecular targets that may offer additive or synergistic neuroprotection to TH, and the need for larger powered clinical trials to determine the dose and timing of administration at which maximal clinical benefits are observed for adjuvant neuroprotectants.

Neuroprotective therapies in the NICU in term infants: present and future

Outcomes of neonatal encephalopathy (NE) have improved since the widespread implementation of therapeutic hypothermia (TH) in high-resource settings. While TH for NE in term and near-term infants has proven beneficial, 30-50% of infants with moderate-to-severe NE treated with TH still suffer death or significant impairments. There is therefore a critical need to find additional pharmacological and non-pharmacological interventions that improve the outcomes for these children. There are many potential candidates; however, it is unclear whether these interventions have additional benefits when used with TH. Although primary and delayed (secondary) brain injury starting in the latent phase after HI are major contributors to neurodisability, the very late evolving effects of tertiary brain injury likely require different interventions targeting neurorestoration. Clinical trials of seizure management and neuroprotection bundles are needed, in addition to current trials combining erythropoietin, stem cells, and melatonin with TH. IMPACT: The widespread use of therapeutic hypothermia (TH) in the treatment of neonatal encephalopathy (NE) has reduced the associated morbidity and mortality. However, 30-50% of infants with moderate-to-severe NE treated with TH still suffer death or significant impairments. This review details the pathophysiology of NE along with the evidence for the use of TH and other beneficial neuroprotective strategies used in term infants. We also discuss treatment strategies undergoing evaluation at present as potential adjuvant treatments to TH in NE.

Combination of stem cell therapy and acupuncture to treat ischemic stroke: a prospective review

Stroke is the second leading cause globally that leads to severe disability and death. Stem cell therapy has been developed over the recent years to treat stroke and diminish the mortality and disability rate of brain injuries. Acupuncture, which can activate endogenous recovery via physical stimuli, has been applied to enhance the recovery and rehabilitation of stroke patients. Attempts have been made to combine stem cell therapy and acupuncture to treat stroke patients and have shown the promising results. This prospective review will look into the possible mechanisms of stem cell therapy and acupuncture and intend to undercover the potential benefit of the combined therapy. It intends to bridge the modern emerging stem cell therapy and traditional acupuncture at cellular and molecular levels and to demonstrate the potential benefit to improve clinical outcomes.

Umbilical cord blood stem cell therapy in premature brain injury: Opportunities and challenges

Preterm birth and associated brain injury are the primary cause of cerebral palsy and developmental disabilities and are among the most serious global health issues that modern society faces. Current therapy for infants suffering from premature brain injury is still mainly supportive, and there are no effective treatments. Thus there is a pressing need for comparative and translational studies on how to reduce brain injury and to increase regeneration and brain repair in preterm infants. There is strong supporting evidence for the use of umbilical cord blood (UCB)-derived stem cell therapy for treating preterm brain injury and neurological sequelae. UCB-derived stem cell therapy is effective in many animal models and has been shown to be feasible in clinical trials. Most of these therapies are still experimental, however. In this review, we focus on recent advances on the efficacy of UCB-derived stem cell therapy in preterm infants with brain injury, and discuss the potential mechanisms behind their therapeutic effects as well as application strategies for future preclinical and clinical trials.

Human Cord Blood-Derived Unrestricted Somatic Stem Cell Infusion Improves Neurobehavioral Outcome in a Rabbit Model of Intraventricular Hemorrhage

Intraventricular hemorrhage (IVH) is a severe complication of preterm birth, which leads to hydrocephalus, cerebral palsy, and mental retardation. There are no available therapies to cure IVH, and standard treatment is supportive care. Unrestricted somatic stem cells (USSCs) from human cord blood have reparative effects in animal models of brain and spinal cord injuries. USSCs were administered to premature rabbit pups with IVH and their effects on white matter integrity and neurobehavioral performance were evaluated. USSCs were injected either via intracerebroventricular (ICV) or via intravenous (IV) routes in 3 days premature (term 32d) rabbit pups, 24 hours after glycerol‐induced IVH. The pups were sacrificed at postnatal days 3, 7, and 14 and effects were compared to glycerol‐treated but unaffected or nontreated control. Using in vivo live bioluminescence imaging and immunohistochemical analysis, injected cells were found in the injured parenchyma on day 3 when using the IV route compared to ICV where cells were found adjacent to the ventricle wall forming aggregates; we did not observe any adverse events from either route of administration. The injected USSCs were functionally associated with attenuated microglial infiltration, less apoptotic cell death, fewer reactive astrocytes, and diminished levels of key inflammatory cytokines (TNFα and IL1β). In addition, we observed better preservation of myelin fibers, increased myelin gene expression, and altered reactive astrocyte distribution in treated animals, and this was associated with improved locomotor function. Overall, our findings support the possibility that USSCs exert anti‐inflammatory effects in the injured brain mitigating many detrimental consequences associated with IVH. stem cells translational medicine2019;8:1157–1169

Clinical Cell Therapy Guidelines for Neurorestoration (IANR/CANR 2017)

Cell therapy has been shown to be a key clinical therapeutic option for central nervous system diseases or damage. Standardization of clinical cell therapy procedures is an important task for professional associations devoted to cell therapy. The Chinese Branch of the International Association of Neurorestoratology (IANR) completed the first set of guidelines governing the clinical application of neurorestoration in 2011. The IANR and the Chinese Association of Neurorestoratology (CANR) collaborated to propose the current version "Clinical Cell Therapy Guidelines for Neurorestoration (IANR/CANR 2017)". The IANR council board members and CANR committee members approved this proposal on September 1, 2016, and recommend it to clinical practitioners of cellular therapy. These guidelines include items of cell type nomenclature, cell quality control, minimal suggested cell doses, patient-informed consent, indications for undergoing cell therapy, contraindications for undergoing cell therapy, documentation of procedure and therapy, safety evaluation, efficacy evaluation, policy of repeated treatments, do not charge patients for unproven therapies, basic principles of cell therapy, and publishing responsibility.

Effect of human umbilical cord blood-derived mononuclear cells on diabetic nephropathy in rats

Diabetic nephropathy (DN) is damage to the kidney which can lead to chronic renal failure, eventually requiring dialysis. Diabetes mellitus is the most common cause of adult kidney failure worldwide in the developed world. The current work was designed to elucidate the effect of mononuclear cells (MNCs) injection on reverse DN in rats exposed to streptozotocin (STZ) injection compared to metformin as a known hypoglycemic drug, 40 Male rats were divided equally into 4 groups; normal control group, diabetic control group, MNCs group were diabetic rats treated with MNCs (30×10⁶ MNCs/rat once iv dose) in the tail vein of the rat, and metformin group were diabetic rats treated with metformin (100mg/kg orally daily dose) for four weeks. The results indicated an improvement effect of MNCs and metformin on STZ-induced DN in rats, which was evidenced by significant decrease in urinary albumin/creatinine ratio, N-acetyl-β-d-glucosaminidase (NAG), urinary kidney injury molecule-1 (KIM-1), serum urea, serum creatinine and fasting blood glucose and significant increase in C- peptide level, compared to diabetic control group. Additionally MNCs treated group exhibited pronounced effects in all previous parameters compared to metformin treated group. It is proved that MNCs treatment was superior to metformin in controlling hyperglycemia, and improving renal function in diabetic rats.

Intraarterial transplantation of human umbilical cord blood mononuclear cells in hyperacute stroke improves vascular function

Background

Human umbilical cord blood (hUCB) cell therapy is a promising treatment for ischemic stroke. The effects of hyperacute stem cell transplantation on cerebrovascular function in ischemic stroke are, however, not well understood. This study evaluated the effects of hyperacute intraarterial transplantation of hUCB mononuclear cells (MNCs) on cerebrovascular function in stroke rats using serial magnetic resonance imaging (MRI).

Methods

HUCB MNCs or vehicle were administered to stroke rats via the internal carotid artery immediately after reperfusion at 60 min following ischemia onset. Lesion volumes were longitudinally evaluated by MRI on days 0, 2, 14, and 28 after stroke, accompanied by behavioral tests. Cerebral blood flow (CBF) and cerebrovascular reactivity were measured by perfusion MRI and CO₂ functional MRI (fMRI) at 28 days post-stroke; corresponding vascular morphological changes were also detected by immunohistology in the same animals.

Results

We found that CBF to the stroke-affected region at 28 days was improved (normalized CBF value: 1.41 ± 0.30 versus 0.49 ± 0.07) by intraarterial transplantation of hUCB MNCs in the hyperacute stroke phase, compared to vehicle control. Cerebrovascular reactivity within the stroke-affected area, measured by CBF fMRI, was also increased (35.2 ± 3.5% versus 12.8 ± 4.3%), as well as the corresponding cerebrovascular density. Some engrafted cells appeared with microvascular-like morphology and stained positive for von Willebrand Factor (an endothelial cell marker), suggesting they differentiated into endothelial cells. Some engrafted cells also connected to host endothelial cells, suggesting they interacted with the host vasculature. Compared to the vehicle group, infarct volume at 28 days in the stem cell treated group was significantly smaller (160.9 ± 15.7 versus 231.2 ± 16.0 mm³); behavioral deficits were also markedly reduced by stem cell treatment at day 28 (19.5 ± 1.0% versus 30.7 ± 4.7% on the foot fault test; 68.2 ± 4.6% versus 86.6 ± 5.8% on the cylinder test). More tissue within initial perfusion-diffusion mismatch was rescued in the treatment group.

Conclusions

Intraarterial hUCB MNC transplantation during the hyperacute phase of ischemic stroke improved cerebrovascular function and reduced behavioral deficits and infarct volume.

Brain damage resulting from postnatal hypoxic-ischemic brain injury is reduced in C57BL/6J mice as compared to C57BL/6N mice

Perinatal hypoxia is a critical complication during delivery and is mostly studied in animal models of postnatal hypoxic-ischemic brain injury. We here studied the effects of postnatal hypoxic-ischemic brain injury in two different sub-strains of C57BL/6 mice, i.e. C57BL/6J and C57BL/6N mice. These two sub-strains show different metabolic properties, for instance an impaired glucose tolerance in C57BL/6J mice. Genetically, this was linked to differences in their nicotinamide nucleotide transhydrogenase (Nnt) genes: In C57BL/6J mice, exons 7-11 of the Nnt gene are deleted, resulting in the absence of functional Nnt protein. The mitochondrial Nnt-protein is one of several enzymes that catalyses the generation of NADPH, which in turn is important for the elimination of reactive oxygen species (ROS). As ROS is thought to contribute to the pathophysiology of hypoxia-ischemia, the lack of Nnt might indirectly increase ROS levels and therefore result in increased brain damage. We therefore hypothesize that lesion score and lesion size will increase in C57BL/6J mice as compared to C57BL/6N mice. Surprisingly, the results showed exactly the opposite: C57BL/6J mice showed a decrease in lesion score and size, associated with a reduced number of apoptotic cells and activated microglia. In contrast, the number of cells with ROS-induced DNA modifications (detected by 8OHdG) was higher in C57BL/6J than C57BL/6N mice. In conclusion, C57BL/6J mice showed reduced ischemic consequences after postnatal hypoxic-ischemic brain injury compared to C57BL/6N mice, with the exception of the amount of ROS-induced DNA-damage. These differences might relate to the lack of Nnt, but also to a modified metabolic setting (cardiovascular parameters, oxygen and glucose metabolism, immune function) in C57BL/6J mice.

First Autologous Cord Blood Therapy for Pediatric Ischemic Stroke and Cerebral Palsy Caused by Cephalic Molding during Birth: Individual Treatment with Mononuclear Cells

Intracranial laceration due to traumatic birth injury is an extremely rare event affecting approximately one newborn per a population of 4.5 million. However, depending on the mode of injury, the resulting brain damage may lead to lifelong sequelae, for example, cerebral palsy for which there is no cure at present. Here we report a rare case of neonatal arterial ischemic stroke and cerebral palsy caused by fetal traumatic molding and parietal depression of the head during delivery caused by functional cephalopelvic disproportion due to a “long pelvis.” This patient was treated by autologous cord blood mononuclear cells (45.8 mL, cryopreserved, TNC 2.53 × 10e8) with a remarkable recovery. Active rehabilitation was provided weekly. Follow-up examinations were at 3, 18, 34, and 57 months. Generous use of neonatal head MRI in case of molding, craniofacial deformity, and a sentinel event during parturition is advocated to enhance diagnosis of neonatal brain damage as a basis for fast and potentially causative treatment modalities including autologous cord blood transplantation in a timely manner.

The hematopoietic system in the context of regenerative medicine

Hematopoietic stem cells (HSC) represent the prototype stem cell within the body. Since their discovery, HSC have been the focus of intensive research, and have proven invaluable clinically to restore hematopoiesis following inadvertent radiation exposure and following radio/chemotherapy to eliminate hematologic tumors. While they were originally discovered in the bone marrow, HSC can also be isolated from umbilical cord blood and can be "mobilized" peripheral blood, making them readily available in relatively large quantities. While their ability to repopulate the entire hematopoietic system would already guarantee HSC a valuable place in regenerative medicine, the finding that hematopoietic chimerism can induce immunological tolerance to solid organs and correct autoimmune diseases has dramatically broadened their clinical utility. The demonstration that these cells, through a variety of mechanisms, can also promote repair/regeneration of non-hematopoietic tissues as diverse as liver, heart, and brain has further increased their clinical value. The goal of this review is to provide the reader with a brief glimpse into the remarkable potential HSC possess, and to highlight their tremendous value as therapeutics in regenerative medicine.

Human Umbilical Cord Blood Cells Ameliorate Motor Deficits in Rabbits in a Cerebral Palsy Model

Cerebral palsy (CP) has a significant impact on both patients and society, but therapy is limited. Human umbilical cord blood cells (HUCBC), containing various stem and progenitor cells, have been used to treat various brain genetic conditions. In small animal experiments, HUCBC have improved outcomes after hypoxic-ischemic (HI) injury. Clinical trials using HUCBC are underway, testing feasibility, safety and efficacy for neonatal injury as well as CP. We tested HUCBC therapy in a validated rabbit model of CP after acute changes secondary to HI injury had subsided. Following uterine ischemia at 70% gestation, we infused HUCBC into newborn rabbit kits with either mild or severe neurobehavioral changes. Infusion of high-dose HUCBC (5 × 10(6) cells) dramatically altered the natural history of the injury, alleviating the abnormal phenotype including posture, righting reflex, locomotion, tone, and dystonia. Half the high dose showed lesser but still significant improvement. The swimming test, however, showed that joint function did not restore to naïve control function in either group. Tracing HUCBC with either MRI biomarkers or PCR for human DNA found little penetration of HUCBC in the newborn brain in the immediate newborn period, suggesting that the beneficial effects were not due to cellular integration or direct proliferative effects but rather to paracrine signaling. This is the first study to show that HUCBC improve motor performance in a dose-dependent manner, perhaps by improving compensatory repair processes.

Could cord blood cell therapy reduce preterm brain injury?

Major advances in neonatal care have led to significant improvements in survival rates for preterm infants, but this occurs at a cost, with a strong causal link between preterm birth and neurological deficits, including cerebral palsy (CP). Indeed, in high-income countries, up to 50% of children with CP were born preterm. The pathways that link preterm birth and brain injury are complex and multifactorial, but it is clear that preterm birth is strongly associated with damage to the white matter of the developing brain. Nearly 90% of preterm infants who later develop spastic CP have evidence of periventricular white matter injury. There are currently no treatments targeted at protecting the immature preterm brain. Umbilical cord blood (UCB) contains a diverse mix of stem and progenitor cells, and is a particularly promising source of cells for clinical applications, due to ethical and practical advantages over other potential therapeutic cell types. Recent studies have documented the potential benefits of UCB cells in reducing brain injury, particularly in rodent models of term neonatal hypoxia–ischemia. These studies indicate that UCB cells act via anti-inflammatory and immuno-modulatory effects, and release neurotrophic growth factors to support the damaged and surrounding brain tissue. The etiology of brain injury in preterm-born infants is less well understood than in term infants, but likely results from episodes of hypoperfusion, hypoxia–ischemia, and/or inflammation over a developmental period of white matter vulnerability. This review will explore current knowledge about the neuroprotective actions of UCB cells and their potential to ameliorate preterm brain injury through neonatal cell administration. We will also discuss the characteristics of UCB-derived from preterm and term infants for use in clinical applications.

The potential for cell-based therapy in perinatal brain injuries

Perinatal brain injuries are a leading cause of cerebral palsy worldwide. The potential of stem cell therapy to prevent or reduce these impairments has been widely discussed within the medical and scientific communities and an increasing amount of research is being conducted in this field. Animal studies support the idea that a number of stem cells types, including cord blood and mesenchymal stem cells have a neuroprotective effect in neonatal hypoxia-ischemia. Both these cell types are readily available in a clinical setting. The mechanisms of action appear to be diverse, including immunomodulation, activation of endogenous stem cells, release of growth factors, and anti-apoptotic effects. Here, we review the different types of stem cells and progenitor cells that are potential candidates for therapeutic strategies in perinatal brain injuries, and summarize recent preclinical and clinical studies.

Feasibility of autologous cord blood cells for infants with hypoxic-ischemic encephalopathy

OBJECTIVE

To assess feasibility and safety of providing autologous umbilical cord blood (UCB) cells to neonates with hypoxic-ischemic encephalopathy (HIE).

STUDY DESIGN

We enrolled infants in the intensive care nursery who were cooled for HIE and had available UCB in an open-label study of non-cyropreserved autologous volume- and red blood cell-reduced UCB cells (up to 4 doses adjusted for volume and red blood cell content, 1-5 × 10(7) cells/dose). We recorded UCB collection and cell infusion characteristics, and pre- and post-infusion vital signs. As exploratory analyses, we compared cell recipients' hospital outcomes (mortality, oral feeds at discharge) and 1-year survival with Bayley Scales of Infant and Toddler Development, 3rd edition scores ≥85 in 3 domains (cognitive, language, and motor development) with cooled infants who did not have available cells.

RESULTS

Twenty-three infants were cooled and received cells. Median collection and infusion volumes were 36 and 4.3 mL. Vital signs including oxygen saturation were similar before and after infusions in the first 48 postnatal hours. Cell recipients and concurrent cooled infants had similar hospital outcomes. Thirteen of 18 (74%) cell recipients and 19 of 46 (41%) concurrent cooled infants with known 1-year outcomes survived with scores >85.

CONCLUSIONS

Collection, preparation, and infusion of fresh autologous UCB cells for use in infants with HIE is feasible. A randomized double-blind study is needed.

Intraarterial transplantation of human umbilical cord blood mononuclear cells is more efficacious and safer compared with umbilical cord mesenchymal stromal cells in a rodent stroke model

INTRODUCTION

Stroke is the second leading cause of death worldwide, claims six lives every 60 seconds, and is a leading cause of adult disability across the globe. Tissue plasminogen activator, the only United States Food and Drug Administration (FDA)-approved drug currently available, has a narrow therapeutic time window of less than 5 hours. In the past decade, cells derived from the human umbilical cord (HUC) have emerged as a potential therapeutic alternative for stroke; however, the most effective HUC-derived cell population remains unknown.

METHODS

We compared three cell populations derived from the human umbilical cord: cord blood mononuclear cells (cbMNCs); cord blood mesenchymal stromal cells (cbMSCs), a subpopulation of cbMNCs; and cord matrix MSCs (cmMSCs). We characterized these cells in vitro with flow cytometry and assessed the cells' in vivo efficacy in a 2-hour transient middle cerebral artery occlusion (MCAo) rat model of stroke. cbMNCs, cbMSCs, and cmMSCs were each transplanted intraarterially at 24 hours after stroke.

RESULTS

A reduction in neurologic deficit and infarct area was observed in all three cell groups; however, this reduction was significantly enhanced in the cbMNC group compared with the cmMSC group. At 2 weeks after stroke, human nuclei-positive cells were present in the ischemic hemispheres of immunocompetent stroke rats in all three cell groups. Significantly decreased expression of rat brain-derived neurotrophic factor mRNA was observed in the ischemic hemispheres of all three cell-treated and phosphate-buffered saline (PBS) group animals compared with sham animals, although the decrease was least in cbMNC-treated animals. Significantly decreased expression of rat interleukin (IL)-2 mRNA and IL-6 mRNA was seen only in the cbMSC group. Notably, more severe complications (death, eye inflammation) were observed in the cmMSC group compared with the cbMNC and cbMSC groups.

CONCLUSIONS

All three tested cell types promoted recovery after stroke, but cbMNCs showed enhanced recovery and fewer complications compared with cmMSCs.

Cx43 expression and function in the nervous system-implications for stem cell mediated regeneration

Pathological conditions of the brain such as ischemia cause major sensorimotor and cognitive impairments. In novel therapeutic approaches to brain injury, stem cells have been applied to ameliorate the pathological outcome. In several experimental models, including hypoxia-ischemia and trauma, transplantation of stem cells correlated with an improved functional and structural outcome. At the cellular level, brain insults also change gap junction physiology and expression, leading to altered intercellular communication. Differences in expression in response to brain injury have been detected in particular in Cx43, the major astrocytic gap junction protein, and its overexpression or deletion was associated with the pathophysiological outcome. We here focus on Cx43 changes in host tissue mediated by stem cells. Stem cell-induced changes in connexin expression, and consecutively in gap junction channel or hemichannel function, might play a part in altered cell interaction, intercellular communication, and neural cell survival, and thereby contribute to the beneficial effects of transplanted stem cells.

Umbilical cord blood cells regulate the differentiation of endogenous neural stem cells in hypoxic ischemic neonatal rats via the hedgehog signaling pathway

Transplantation of umbilical cord blood mononuclear cells (UCBMC) promotes the proliferation of endogenous neural stem cells (NSCs), but it has been unclear whether the proliferating NSCs can differentiate into mature neural cells. Therefore, we explored the effects of UCBMC transplantation on the differentiation of endogenous NSCs and their underlying mechanisms. Seven-day-old Sprague-Dawley rats underwent left carotid ligation followed by hypoxic stress. UCBMC were transplanted 24h after hypoxia ischemia (HI). BrdU/β-tubulin/HNA/DAPI, BrdU/GFAP/HNA/DAPI, Ngn1/DAPI, and BMP4/DAPI were measured by immunofluorescence staining; Shh, Gli1, Ngn1, and BMP4 proteins were measured by western-blot analysis 28 days after transplantation. More newborn neurons and fewer astrocytes were observed in the HI+UCBMC group, its neuronal percentage was higher, and glial percentage was lower compared with the N+UCBMC (P<0.05) and HI+PBS groups (P<0.01), while fewer newborn neurons and more newborn astrocytes were found in the HI+cyclopamine (an antagonist of the hedgehog protein)+UCBMC group compared with the HI+UCBMC group (P<0.01). The expression of Shh, Gli1, and Ngn1 proteins was higher and BMP4 protein was lower in the HI+UCBMC compared with the HI+PBS group (P<0.01) and the HI+cyclopamine+UCBMC group (P<0.01). Linear regression analysis showed that the differentiation of NSCs correlated with expression of Ngn1 and BMP4 proteins (P<0.01). In conclusion, UCBMC promote neuronal differentiation and reduce glial differentiation in hypoxic ischemic neonatal rats via the hedgehog signaling pathway.

Autologous cord blood therapy for infantile cerebral palsy: from bench to bedside

About 17 million people worldwide live with cerebral palsy, the most common disability in childhood, with hypoxic-ischemic encephalopathy, preterm birth, and low birth weight being the most important risk factors. This review will focus on recent developments in cell therapy for infantile cerebral palsy by transplantation of autologous umbilical cord blood. There are only 4 publications available at present; however, the observations made along with experimental data in vivo and in vitro may be of utmost importance clinically, so that a review at an early developmental stage of this new therapeutic concept seems justified. Particularly, since the first published double-blind randomized placebo-controlled trial in a paradigm using allogeneic cord blood and erythropoietin to treat cerebral palsy under immunosuppression showed beneficial therapeutic effects in infantile cerebral palsy, long-held doubts about the efficacy of this new cell therapy are dispelled and a revision of therapeutic views upon an ailment, for which there is no cure at present, is warranted. Hence, this review will summarize the available information on autologous cord blood therapy for cerebral palsy and that on the relevant experimental work as far as potential mechanisms and modes of action are concerned.

Transplantation of cryopreserved human umbilical cord blood mononuclear cells does not induce sustained recovery after experimental stroke in spontaneously hypertensive rats

Previous studies have highlighted the enormous potential of cell-based therapies for stroke not only to prevent ischemic brain damage, but also to amplify endogenous repair processes. Considering its widespread availability and low immunogenicity human umbilical cord blood (HUCB) is a particularly attractive stem cell source. Our goal was to investigate the neurorestorative potential of cryopreserved HUCB mononuclear cells (MNC) after permanent middle cerebral artery occlusion (MCAO) in spontaneously hypertensive rats (SHR). Human umbilical cord blood MNC or vehicle solution was administered intravenously 24 hours after MCAO. Experimental groups were as follows: (1) quantitative polymerase chain reaction (PCR) of host-derived growth factors up to 48 hours after stroke; (2) immunohistochemical analysis of astroglial scarring; (3) magnetic resonance imaging (MRI) and weekly behavioral tests for 2 months after stroke. Long-term functional outcome and lesion development on MRI were not beneficially influenced by HUCB MNC therapy. Furthermore, HUCB MNC treatment did not change local growth factor levels and glial scarring extent. In summary, we could not demonstrate neurorestorative properties of HUCB MNC after stroke in SHR. Our results advise caution regarding a prompt translation of cord blood therapy into clinical stroke trials as long as deepened knowledge about its precise modes of action is missing.

Effects of intravenous human umbilical cord blood CD34+ stem cell therapy versus levodopa in experimentally induced Parkinsonism in mice

INTRODUCTION

Parkinsonism is a neurodegenerative disease with impaired motor function. The current research was directed to investigate the effect of CD34+ stem cells versus levodopa in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinsonism.

MATERIAL AND METHODS

Mice were divided into 4 groups; saline-injected, MPTP: received four MPTP injections (20 mg/kg, i.p.) at 2 h intervals, MPTP groups treated with levodopa/carbidopa (100/10 mg/kg/twice/day for 28 days) or single intravenous injection of 10(6) CD34+ stem cells/mouse at day 7 and allowed to survive until the end of week 5.

RESULTS

Levodopa and stem cells improved MPTP-induced motor deficits; they abolished the difference in stride length, decreased percentage of foot slip errors and increased ambulation, activity factor and mobility duration in parkinsonian mice (p < 0.05). Further, they significantly (p < 0.05) increased striatal dopamine (85.3 ±4.3 and 110.6 ±5.3) and ATP levels (10.6 ±1.1 and 15.5 ±1.14) compared to MPTP (60.1 ±3.9 pmol/g and 3.6 ±0.09 mmol/g, respectively) (p < 0.05). Moreover, mitochondrial DNA from mice treated with levodopa or stem cells was in intact form; average concentration was (52.8 ±3.01 and 107.8 ±8.6) and no appreciable fragmentation of nuclear DNA was found compared to MPTP group. Regarding tyrosine hydroxylase (TH) immunostaining, stem cell group showed a marked increase of percentage of TH-immunopositive neurons (63.55 ±5.2) compared to both MPTP (37.6 ±3.1) and levodopa groups (41.6 ±3.5).

CONCLUSIONS

CD34+ cells ameliorated motor, biochemical and histological deficits in MPTP-parkinsonian mice, these effects were superior to those produced by levodopa that would be promising for the treatment of PD.

Recovery of fine motor performance after ischemic damage to motor cortex is facilitated by cell therapy in the rhesus monkey

We investigated the efficacy on recovery of function following controlled cortical ischemia in the monkey of the investigational cell drug product, CNTO 0007. This drug contains a cellular component, human umbilical tissue-derived cells, in a proprietary thaw and inject formulation. Results demonstrate significantly better recovery of motor function in the treatment group with no difference between groups in the volume or surface area of ischemic damage, suggesting that the cells stimulated plasticity.

Standard recommendations for the application of Chinese clinical cell therapy for neurorestoration (2012)

Cell therapy has been shown to be a promising alternative therapy for neurorestoration, and more than 30 different types of cells have been shown to possess some capability to restore lost or damaged neurological functions. Chinese physicians have successfully applied cell therapy to many neurological diseases and damages in the clinic and contributed to establish a discipline of neurorestoratology. To standardize the clinical procedures of cell therapy as one of the strategies for treating neurological disorders, the Chinese Branch of the International Association of Neurorestoratology (IANR) and the Preparatory Committee of Chinese Association of Neurorestoratology recently completed the Standard Recommendations (2012) for the Application of Chinese Clinical Cell Therapy for Neurorestoration. We hope these recommendations will guide clinical practice in applying cell therapy for neurorestoration, which will therein offer a reference for both Chinese and other countries' governments to make relevant official regulations. This manuscript is published as part of the International Association of Neurorestoratology (IANR) supplement issue of Cell Transplantation.

Modulation of physical environment makes placental mesenchymal stromal cells suitable for therapy

Low level of oxygen at the site of injury is likely to affect the viability and proliferation of the transplanted mesenchymal stromal cells (MSCs). Hence there is a need to understand the effect of the physical environment on transplanted stromal cells. Therefore, we have studied the effect of the duration of hypoxic exposure alone or in combination with normoxia on placenta derived mesenchymal stem cell (PDMSCs). PDMSCs and bone marrow MSCs (BMMSCs) were analysed under four different culture conditions, exposure to direct normoxia (N), direct hypoxia (H) and intermittent normoxia followed by hypoxia (NH) and intermittent hypoxia followed by normoxia (HN). The effect on morphology, proliferation, metabolic activity by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide) and viability by 7AAD (7-amino-actinomycin D) were assayed, along with markers for MSCs and HLADR. No change in morphology, marker expression or HLADR was detected in N, H, NH or HN. An increase in proliferation rate, decrease in population doubling-time (PDT) and a relative increase in metabolic activity was strongly noted in the order: NH, N/HN and H. No significant difference was observed in the viability between N, H, NH or HN. A similar pattern was also observed in BMMSCS, indicating comparable suitability of PDMSCs in therapeutic applications. Thus we conclude that intermittent exposure to normoxia prior to hypoxic exposure is a better option than direct exposure to hypoxia. This may have clinical relevance in that they probably mirror the in vivo scenario of systemic delivery (NH) of cells as opposed to local delivery (H), thereby suggesting that systemic delivery is better than local delivery.

First autologous cell therapy of cerebral palsy caused by hypoxic-ischemic brain damage in a child after cardiac arrest-individual treatment with cord blood

Each year, thousands of children incur brain damage that results in lifelong sequelae. Therefore, based on experimental evidence, we explored the therapeutic potential of human cord blood, known to contain stem cells, to examine the functional neuroregeneration in a child with cerebral palsy after cardiac arrest. The boy, whose cord blood was stored at birth, was 2.5 years old and normally developed when global ischemic brain damage occurred resulting in a persistent vegetative state. Nine weeks later, he received autologous cord blood (91.7 mL, cryopreserved, 5.75 × 10e8 mononuclear cells) intravenously. Active rehabilitation (physio- and ergotherapy) was provided daily, follow-up at 2, 5, 12, 24, 30, and 40 months. At 2-months follow-up the boy's motor control improved, spastic paresis was largely reduced, and eyesight was recovered, as did the electroencephalogram. He smiled when played with, was able to sit and to speak simple words. At 40 months, independent eating, walking in gait trainer, crawling, and moving from prone position to free sitting were possible, and there was significantly improved receptive and expressive speech competence (four-word sentences, 200 words). This remarkable functional neuroregeneration is difficult to explain by intense active rehabilitation alone and suggests that autologous cord blood transplantation may be an additional and causative treatment of pediatric cerebral palsy after brain damage.

Repairing neural injuries using human umbilical cord blood

Stem cells are promising sources for repairing damaged neurons and glial cells in neural injuries and for replacing dead cells in neurodegenerative diseases. An essential step for stem cell-based therapy is to generate large quantities of stem cells and develop reliable culture conditions to direct efficient differentiation of specific neuronal and glial subtypes. The human umbilical cord and umbilical cord blood (UCB) are rich sources of multiple stem cells, including hematopoietic stem cells, mesenchymal stem cells, unrestricted somatic stem cells, and embryonic-like stem cells. Human UC/UCB-derived cells are able to give rise to multiple cell types of neural lineages. Studies have shown that UCB and UCB-derived cells can survive in injured sites in animal models of ischemic brain damage and spinal cord injuries, and promote survival and prevent cell death of local neurons and glia. Human UCB is easy to harvest and purify. Moreover, unlike embryonic stem cells, the use of human UCB is not limited by ethical quandaries. Therefore, human UCB is an attractive source of stem cells for repairing neural injuries.

Proteomic analysis of alterations induced by perinatal hypoxic-ischemic brain injury

Perinatal hypoxic-ischemic brain injury is an important cause of neurological deficits still causing mortality and morbidity in the early period of life. As efficient clinical or pharmaceutical strategies to prevent or reduce the outcome of perinatal hypoxic-ischemic brain damage are limited, the development of new therapies is of utmost importance. To evolve innovative therapeutic concepts, elucidation of the mechanisms contributing to the neurological impairments upon hypoxic-ischemic brain injury is necessary. Therefore, we aimed for the identification of proteins that are affected by hypoxic-ischemic brain injury in neonatal rats. To assess changes in protein expression two days after induction of brain damage, a 2D-DIGE based proteome analysis was performed. Among the proteins altered after hypoxic-ischemic brain injury, Calcineurin A, Coronin-1A, as well as GFAP were identified, showing higher expression in lesioned hemispheres. Validation of the changes in Calcineurin A expression by Western Blot analysis demonstrated several truncated forms of this protein generated by limited proteolysis after hypoxia-ischemia. Further analysis revealed activation of calpain, which is involved in the limited proteolysis of Calcineurin. Active forms of Calcineurin are associated with the dephosphorylation of Darpp-32, an effect that was also demonstrated in lesioned hemispheres after perinatal brain injury.

Changes in Interleukin-1 alpha serum levels after transplantation of umbilical cord blood cells in a model of perinatal hypoxic-ischemic brain damage

Transplantation of human umbilical cord blood (hUCB) cells is a potential approach for the treatment of perinatal hypoxic-ischemic brain injury. Neurological and motor deficits resulting from the brain lesion are ameliorated upon transplantation. The molecular mechanisms underlying these improvements are currently being unravelled. One parameter identified as part of the beneficial effects of hUCB cells is the reduction of brain inflammation. It is, however, unclear whether the modulation of brain inflammation is due to local or systemic effects of hUCB cells. In this study, the effects of hUCB cell transplantation in a model of perinatal hypoxic-ischemic brain injury were investigated at the systemic level by measurement of serum levels of pro-inflammatory cytokines by multiplex bead arrays. Two days after induction of the brain damage, levels of the pro-inflammatory cytokines Interleukin-1α (IL-1α), Interleukin-1β (IL-1β), and Tumor necrosis factor α (TNFα) were increased in the serum of rats. Application of hUCB cells, in turn, correlated with a reduced elevation of serum levels of these pro-inflammatory cytokines. This decrease was accompanied by a reduced expression of CD68, a marker protein of activated microglia/macrophages in the brain. Therefore, systemic modulation of the immune response by hUCB cells could represent one possible mechanism of how these cells might mediate their beneficial effects. Creation of a regenerative environment with reduced inflammation might account for the functional regeneration observed upon hUCB cell treatment in lesioned animals.

Transplantation of human umbilical cord blood cells mediated beneficial effects on apoptosis, angiogenesis and neuronal survival after hypoxic-ischemic brain injury in rats

Transplantation of human umbilical cord blood (hucb) cells in a model of hypoxic-ischemic brain injury led to the amelioration of lesion-impaired neurological and motor functions. However, the mechanisms by which transplanted cells mediate functional recovery after brain injury are largely unknown. In this study, the effects of hucb cell transplantation were investigated in this experimental paradigm at the cellular and molecular level. As the pathological cascade in hypoxic-ischemic brain injury includes inflammation, reduced blood flow, and neuronal cell death, we analyzed the effects of peripherally administered hucb cells on these detrimental processes, investigating the expression of characteristic marker proteins. Application of hucb cells after perinatal hypoxic-ischemic brain injury correlated with an increased expression of the proteins Tie-2 and occludin, which are associated with angiogenesis. Lesion-induced apoptosis, determined by expression of cleaved caspase-3, decreased, whereas the number of vital neurons, identified by counting of NeuN-positive cells, increased. In addition, we observed an increase in the expression of neurotrophic and pro-angiogenic growth factors, namely BDNF and VEGF, in the lesioned brain upon hucb cell transplantation. The release of neurotrophic factors mediated by transplanted hucb cells might cause a lower number of neurons to undergo apoptosis and result in a higher number of living neurons. In parallel, the increase of VEGF might cause growth of blood vessels. Thus, hucb transplantation might contribute to functional recovery after brain injury mediated by systemic or local effects.